Frame jibs for coal cutting machines



1961 s. E. PROCTOR 2,998,235

FRAME JIBS FOR COAL CUTTING MACHINES Filed Aug. 25, 1960 2 Sheets-Sheet 1 a a/wnpzajuw [um Amara/e r;

Aug. 29, 1961 s. E. PROCTOR 2,998,235

FRAME J 1135 FOR COAL CUTTING MACHINES Filed Aug. 25, 1960 2 Sheets-Sheet 2 I Ali/6W 46 um, 64, M *4/41;

r 2,998,235 lc Patented Aug. 29, 1961 2,998,235 FRAME JIBS FOR COAL CUTTING MACHINES Sidney Ernest Proctor, Saundert'on, High Wycombe, England, assignor to Austin Hoy and Company Limited, High Wycombe, England, a company of Great Britain Filed Aug. 25,1960, Ser. No. 51,982 Claims priority, application Great Britain Aug. 27, 1959 -1 Claim. (Cl. 262- 30) This invention comprises improvements in or relating to frame jibs for coal cutting machines.

In our copending patent application No. 41,099 there is described a coal-cutting machine in which a sprocket on the side of the body of the machine is rotated about a horizontal axis and drives a chain which is capable of bending not only in the plane of the sprocket but also in a plane at right angles thereto. The chain runs on a frame jib which, near the sprocket, is arranged in a plane coinciding with the plane of the sprocket teeth but which, at a little distance from the sprocket, has two horizontal arms bent outwardly away from the coal cutting machine, one near the ground and the other near the top of the seam of coal, the arms being united by a vertical section joining their ends so that the jib with the chain upon it, when the latter is running, cuts out a rectangular block of coal from the seam beside the machine and allows the coal, as it breaks off from the block due to its weight, to lie beside the track along which the machine is progressing. Y

The present invention has for its object to provide an improved form of frame jib. It is necessary that the jib should be collapsible so that after a out has been taken it can be flitted back to its starting point without the up per arm of the jib fouling the TOOEf of the coal scam. With the constructions described in the aforesaid application however, when the jib, after being collapsed, is extended again for its working stroke, there is a distinct gap between the top and lower halves of the jib frame which exposes the chain to undue wear.

Accordingly the present invention provides a coal-cutting machine having a body with a horizontal sprocketcarrying shaft projecting laterally therefrom, a frame-jib secured to the body so as to project laterally therefrom with horizontal top and bottom arms and an intermediate side-portion interconnecting the top and bottom arms and spaced from the body, a chain guide on the jib extending along its arms and intermediate side portion, and an endless cutter-chain driven by the sprocket and running in the chain guide on the jib, characterised in that the intermediate sideportion comprises tWOl portions hinged to one another and to the top and bottom half of the frame and in that the frame-jib can be collapsed by relative movement of the top arm and the bottom arm while the two portions of the intermediate side portion fold together. The chain can adapt itself to the folded shape of the vertical portion of the jib by bending round the hinge and preferably the hinged portions are provided with side plates which help to keep the chain in situ when the section is folded. The important point is that the intermediate side-portion is kept without any gap when it is straightened for use in cutting coal.

Two constructions of coal-cutting machine embodying the invention will now be described by way of example only and with reference to the accompanying drawings in which:

FIGURE 1 is a perspective view from the rear of a portion of one coal-cutting machine showing the construction of the jib,

FIGURE 2 is a perspective view of the parts shown in FIGURE 1 but with the jib collapsed, and

FIGURE 3 is a side view of a second coal-cutting machine.

In this example shown in FIGURES '1 and 2, the body 11 of the coal-cutting machine comprises a long low rectangular casing in which is located a driving motor and trom which projects at oneside near one end a sprocket shaft 12 driven by the motor. On the shaft is a cutterchain driving sprocket 20 (FIG. 1); this sprocket is removed in FIGURES 2 and 3 of the drawings and is partly broken away in FIG. 1 so that the mounting of the frame-jib may be seen clearly.

There is secured to the side of the machine a boss 13 which houses a bearing for the sprocket shaft. The boss is formed with a groove 14 of dove-tail section, which extends around a part of the periphery of the boss. A bracket '15 is formed with a tongue 16 of dove-tail section which describes an are having the same curvature as the peripheral groove 14. The tongue 16 slides in the groove 14 so that the bracket 15 can be rotated around the outside of the boss about the axis of the sprocket shaft. The bracket 15 is formed with an arm 17 in the shape of a flat plate close to the side of the body of the machine. Secured to the side of the body of the machine there is a vertical support-plate 18 to which the flat arm 17 on the bracket can be bolted, the bolt-holes (not shown) being located so that when the bolts are in position the arm will be held in its upper position as shown in FIGURE 1. The arm '17 carries a. guide 19 which is T-shaped in section and, slidably mounted on the T-shapcd guide 19, is the root portion 21 of an upper horizontal jib-section 22. The root portion 21 carries a chain guide and is shaped so that the chain guide is tangential to the sprocket on the sprocket shaft, so that it can receive the chain from the sprocket.

Lower down the support plate, there is another T-shaped guide 23 which supports the root portion 24 of a lower horizontal jib-section '25; this root portion 24 is also positioned so that a chain guide upon it is tangential to the sprocket but on the underside thereof. The upper and lower horizontal jib sections are at right angles to the plane of the chain guides on the root portions and carry chain guides which are curved into the chain guides on the root portions. The ends of these horizontal upper and lower jib-sections 22, 25 are curved towards one another and they are joined together by a vertical section consisting of two portions 26, 27 (see FIGURE 2) hinged one to the other and to the ends of the upper and lower horizontal sections. These two side portions 26, 27 carry side plates 28 to keep the chain securely on them even if they are folded together to collapse the jib. In normal running however, the portions 26, 27 are in line with each other and are held in line by a vertical plate 29 which joins together their three hinge pins 31, 32 and 33.

If the jib is to be collapsed the vertical plate 29 is removed and the bolts which secure the flat arm 17 on the rotatable bracket to the support plate 18 on the side of the coal-cutting machine are removed; the jib is then collapsed by bending the portions 26, 27 of the vertical section towards the coal-cutter machine. This movement is permitted by the bracket 15 on the boss 13 rotating about the axis of the sprocket shaft. After flitting, the jib is extended by straightening the hinged portions 26, 27, applying the plate 29 which looks the three hingepins in line with one another, and bolting the flat arm 17 to the support plate.

In the construction shown in FIGURE 3 a coa=l-cutter machine comprises a rectangular body 31 containing a motor and a drive for a sprocket, the shaft 32 to which is at right angles to the length of the body of the machine and overhangs at one side, the sprocket (not shown) being mounted on the end of the shaft. To the side of the machine there is bolted a large flat flange 33 close to the chain drive sprocket, which flange contains two arcuate slots 34, 35 concentric with the sprocket shaft 32. The flange is secured to the machine by studs 36 which pass through the slots and nuts 37 on the ends of the studs. On the upper part of the flange there is formed the first section 38 of the frame jib, containing a guide 40 for the chain, which is tangential to the sprocket so that it can receive the chain accurately. Owing to the arcuate form of the slots 34, 35, the angle of the guide relatively to the sprocket, will be the same in all positions. 'On-the flange and in line with the initial part of bhe chain guides, there is secured the upper horizontal section 39 of the frame jib containing a chain guide 41 which aligns with the initial part 40 of the chain guide on the flange.

at right angles to the length of the coal-cutter machine, and then downwardly to join -a vertical section (not shown) which corresponds with the vertical section shown 'in FIGURES 1 and 2. The lower part of the jib, which is fixed to the machine, without adjustability, comprises a section 42 to deliver the chain to the sprocket and a portion 43 bent outwardly to run beneath the coal scam, the end of which bends upwardly behind the coal seam towards the downwardly projecting portion of the upper horizontal section of the jib. The upwardly and down- 'ward'ly extending portions of the horizontal jib sections 'arm 47, the end of the lever am being connected by a length 48 to the flange. A square on the end of the worm-shaft 49 permits it to be engaged by a key, and

The upper horizontal section of the jib is bent outwardly the operator, after loosening the nuts which hold the flange to the 'body of the machine and removing the vertical plate which holds the hinged side portions in alignment, is able to lower the flange 33 by operating the worm by the key. The flange 33 is guided in its movement by the studs 36 which slide in the arcuate slots 34, 35; consequently the chain guide remains tangential to the chain-driving sprocket. By lowering the flange 33 the upper horizontal jib-section 39 is lowered towards the lower horizontal jib-section 43, thus causing the hinged side portions of the jib to fold together and the jib to collapse.

I claim:

A coal-cutting machine comprising in combination a body, a horizontal sprocket shaft projecting laterally therefrom, a sprocket thereon, a frame jib having a horizontal lower arm projecting laterally from the body, a horizontal upper arm likewise projecting laterally from the body and connected to the body by a bracket mounted on guide means concentric with the sprocket so that the arm can be adjusted up and down relatively to the body by movement around the sprocket on the guide means, an intermediate side-portion to the jib connecting together the outer ends of the lower and upper arms, the intermediate portion being movable to permit said adjustment up and down of the upper arm, a chain guide channel extending along said upper and lower arms and intermediate portion, and an end-less cutter chain extending around the sprocket and along said upper and lower arms and inter-mediate portion, in said guidechannel.

References Cited in the file of this patent UNITED STATES PATENTS 2,189,670 Lewis Feb. 6, 1940 

